From TF2 Wiki
The Sniper rifle is the primary weapon for the Sniper class. It has perfect accuracy, no damage falloff, and was the first weapon with a zoom sight. The Sniper rifle must be charged for full effectiveness. The zoom display features a charge meter and a small red or blue dot in the center to aid in aiming. When zoomed, the charge meter increases gradually from 0% to 100%. At the same time the target dot will change from a dull color to bright red / blue. It takes 4 seconds for a full charge. The charge meter resets after a shot is fired or when the scope is unzoomed. Charge is not built up while not zoomed. Zoom is activated when the secondary function is used (default: Mouse2 for PC, Left Trigger for Xbox 360 and L2 for PS3). Movement speed is slowed while zoomed in to 27%, and slowed even further to 0.01% when crouching. You cannot be zoomed in while jumping or falling. A killing shot to the head while zoomed in will result in a Headshot and will display a different icon where the kill is reported. A Headshot is a guaranteed Critical hit and is furthermore the only way for the Sniper rifle to score a Critical hit (except during Humiliation or a Kritzkrieg). When zoomed, a team-colored dot will appear on walls or floors (or wherever the rifle is aiming), alerting observant opponents to the Sniper. Firing the Sniper rifle when not zoomed will still damage the target, but for very little.
- Base: 50 (0% charge or unscoped), 150 (100% charge)
- Bodyshot: 43-57 (0% charge or unscoped), 128-172 (100% charge)
- Mini-Crit: 67.5 (0% charge or unscoped), 202.5 (100% charge)
- Headshot (scoped only): 150 (0% charge), 450 (100% charge)
- Critical hit (humiliation or Kritzkrieg only): 150
Note: Distance from the target does not affect the Sniper rifle's damage. Damages are approximate and determined by community testing.
- Attack Interval: 1.5
- There is a 200 ms delay before a zoomed Sniper shot can get a Critical hit. 
- There is a 1 second delay before the damage of a zoomed Sniper shot increases.
All times are in seconds. Times are approximate and determined by community testing.|
- This rifle appears to be based on the former sniping rifle of the Australian military, the British-made Parker-Hale M82. It was replaced around the end of the millennium with a modified, locally manufactured version of the Accuracy International Arctic Warfare rifle named the SR-98, however, the M82 still sees occasional training use in Reserve units, and is popular with collectors.
- the Sniper rifle has no magazine instead, the sniper very quickly cycles the bolt and inserts a new round in the chamber simultaneously.
- The Sniper rifle has Developer weapon variants.
- The laser between the scope and the barrel does not actually have a texture, only a small hole in the center.
- After the recent Engineer update, the Sniper Rifle's headshot kill icon has seemed to have changed from the headshot where blood is splattered behind to the head to an icon where the blood is splattered in front of the head. This icon is somewhat similar to the headshot kill icon of the Ambassador.
- The Sniper rifle appears to be bolt-action, which is the most common action amongst modern sniper rifles.
- The Sniper Rifle can shoot and destroy Sticky bombs
- No Sniper rifle can ever randomly crit.
English • русский